I have been on 40mg of amphetamine for lack of cognative function for 8 years. This my have been an accurate diagnosis or may be due to other drugs I m on or lack of sleep. I was researching amphetamine class drugs and was socked to find how dangerous amphetamine class drugs react with just about everything else. I immediately began slowly reducing my 40mg to 15mgs, by 5mg per week dosages. But l ve hit a brick wall. Anything lower causes that old familiar missed a dose withdrawal, climb the walls reaction. My Dr. is useless. Can you help.